Try to get your money to zero before reaching the coffee shop! That's the only hint I can give, sorry. Good luck!
Hmm. To be honest, there may be combinations even I don't know about, but Stexe mentioned one choice that is very useful. Apart from that, just some general guidance...
- There are certain cases where you don't need to exhaust the full list of options to advance to the next leg of the story. Try looking for opportunities to skip ahead sooner.
- There's no real nickel-and-dime-ing involved. You only need to click on a handful of options and most of them are big-ticket items (that is, in the billions).
- If you've EARNED money at any point (by going to the bathroom, talking with your nibling, etc), you can't access the secret endings at all and will need to rewind or start over.
I hope that helps a little. Good luck!